1// SPDX-License-Identifier: Zlib
  2#ifndef DFLTCC_UTIL_H
  3#define DFLTCC_UTIL_H
  4
  5#include <linux/zutil.h>
  6
  7/*
  8 * C wrapper for the DEFLATE CONVERSION CALL instruction.
  9 */
 10typedef enum {
 11    DFLTCC_CC_OK = 0,
 12    DFLTCC_CC_OP1_TOO_SHORT = 1,
 13    DFLTCC_CC_OP2_TOO_SHORT = 2,
 14    DFLTCC_CC_OP2_CORRUPT = 2,
 15    DFLTCC_CC_AGAIN = 3,
 16} dfltcc_cc;
 17
 18#define DFLTCC_QAF 0
 19#define DFLTCC_GDHT 1
 20#define DFLTCC_CMPR 2
 21#define DFLTCC_XPND 4
 22#define HBT_CIRCULAR (1 << 7)
 23#define HB_BITS 15
 24#define HB_SIZE (1 << HB_BITS)
 25
 26static inline dfltcc_cc dfltcc(
 27    int fn,
 28    void *param,
 29    Byte **op1,
 30    size_t *len1,
 31    const Byte **op2,
 32    size_t *len2,
 33    void *hist
 34)
 35{
 36    Byte *t2 = op1 ? *op1 : NULL;
 37    size_t t3 = len1 ? *len1 : 0;
 38    const Byte *t4 = op2 ? *op2 : NULL;
 39    size_t t5 = len2 ? *len2 : 0;
 40    register int r0 __asm__("r0") = fn;
 41    register void *r1 __asm__("r1") = param;
 42    register Byte *r2 __asm__("r2") = t2;
 43    register size_t r3 __asm__("r3") = t3;
 44    register const Byte *r4 __asm__("r4") = t4;
 45    register size_t r5 __asm__("r5") = t5;
 46    int cc;
 47
 48    __asm__ volatile(
 49                     ".insn rrf,0xb9390000,%[r2],%[r4],%[hist],0\n"
 50                     "ipm %[cc]\n"
 51                     : [r2] "+r" (r2)
 52                     , [r3] "+r" (r3)
 53                     , [r4] "+r" (r4)
 54                     , [r5] "+r" (r5)
 55                     , [cc] "=r" (cc)
 56                     : [r0] "r" (r0)
 57                     , [r1] "r" (r1)
 58                     , [hist] "r" (hist)
 59                     : "cc", "memory");
 60    t2 = r2; t3 = r3; t4 = r4; t5 = r5;
 61
 62    if (op1)
 63        *op1 = t2;
 64    if (len1)
 65        *len1 = t3;
 66    if (op2)
 67        *op2 = t4;
 68    if (len2)
 69        *len2 = t5;
 70    return (cc >> 28) & 3;
 71}
 72
 73static inline int is_bit_set(
 74    const char *bits,
 75    int n
 76)
 77{
 78    return bits[n / 8] & (1 << (7 - (n % 8)));
 79}
 80
 81static inline void turn_bit_off(
 82    char *bits,
 83    int n
 84)
 85{
 86    bits[n / 8] &= ~(1 << (7 - (n % 8)));
 87}
 88
 89static inline int dfltcc_are_params_ok(
 90    int level,
 91    uInt window_bits,
 92    int strategy,
 93    uLong level_mask
 94)
 95{
 96    return (level_mask & (1 << level)) != 0 &&
 97        (window_bits == HB_BITS) &&
 98        (strategy == Z_DEFAULT_STRATEGY);
 99}
100
101char *oesc_msg(char *buf, int oesc);
102
103#endif /* DFLTCC_UTIL_H */